SM5958 Datasheet, PDF (52/53 Pages) SyncMOS Technologies,Inc – Enhance user code protection

= 0: Disable.
ISPPGS[1:0]: ISP Page Selection.
ISPPGSE, ISPPGS1,ISPPGS0
000
001
010
011
100
101
110
111
SM5958
8-Bit Micro-controller
32KB with ISP Flash
& 1KB RAM embedded
Per page in ISP page erase operation
512Byte
512Byte
512Byte
512Byte
512Byte
256Byte
128Byte
Reserved
ISPF [1:0]: ISP function select bit.
ISPF[1:0]
ISP function
00
Byte program
01
Chip protect
10
Page erase
11
Chip erase
The choice ISP function will start to execute once the software write data to ISPC register.
To perform byte program/page erases ISP function, user need to specify flash address at first. When
performing page erase function, SM5958 will erase entire page which flash address indicated by ISPFAH &
ISPFAL registers located within the page.
To perform the chip erase ISP function, SM5958 will erase all the flash program memory except the ISP
service program space. To perform chip protect ISP function, the SM5958 flash memory content will be read
#00H. The program will miss the interrupt if it happens during the ISP funtion.
e.g. ISP service program to do the byte program - to program #22H to the address $1005H
CLR EA
;disable interrupt
MOV ISPFD, #55h
MOV ISPFD, #0AAh
MOV ISPFD, #55h ; enable ISPE write attribute
ORL SCONF, #04H ; enable ISP function
MOV ISPFAH, #10H ; set flash address-high, 10H
MOV ISPFAL, #05H ; set flash address-low, 05H
MOV ISPFD, #22H ; set flash data to be programmed, data = 22H
MOV ISPC, #80H ; start to program #22H to the flash address $1005H
ANL SCONF, #0FBH ; disable ISP function
SETB EA
; enable interrupt
Specifications subject to change without notice contact your sales representatives for the most recent information.
ISSFD-M089
Ver C SM5958 04/17/2015
- 52 -